I’m pretty sure the definition of ‘situational irony’, as opposed to verbal irony as a rhetorical device, is broad and vague enough to include scenarios like this where the confluence of events and conditions occurs in such a way as to produce amusing coincidence. Particularly in this case, where those events are driven by the actions of one person (the note-writer) who, were he a fictional character, would be neatly fulfilling the definition of dramatic irony.

#9.2 Dr.Chalkwitheringlicktacklefeff – Am on too many pain meds to actually comprehend your post, but I loved the flow of it anyhow, so a thumb your way! Some language usage is gorgeous regardless of content.

I don’t understand why so many comments seem to be explaining the humour of this PAN? Is this seemingly obvious irony more complicated than I realise… or do we have especially stupid commenters online at the moment?

Actually, that’s the point. By saying “this is why it’s funny…” what we’re actually saying is “it’s not funny”. It’s basically a sarcastic way of saying “I see what you did there” when what the joker did there wasn’t funny.